Evaporator



Nov. 18, 1930.

. Hi w. How

EVAPORATOR Filed Jan. 12, 1927 llllll 2 Sheets-Sheet 1 Nbv. 18, 1930. H. w. HOW 1,782,143

EVAPORATOR Filed Jan. 12, 1927 2 Sheets-Sheet 2 a O O O a 0 0 0 0 0 0 2/ o o o o o o o o o o o o o o o o o o o 0 0 0 o o o o o o o o o o o O O o o o o 0 o o o 0 0 0 o I o o o o o o O o o o o o o o o o O 0 0 o o o o o 0 Q o o o o o o o o o o 0 0 ooo oo/-- oo0o 00 as 000080 8 \oogogogoooo O O 08888888 {7 988 88888o 0 8080 080 r 23 8 8 8 8 o 0 0 o I I o o o o o o o o o\ :o 0 0 0 0 0 0 0 0 0 o o o o o 2/ o o 'o o ,8 o O 0 0 o o o o o o 0 0 0 0 o o o o o 3 c5 o o o o 0 o o o o o o o o o o o o o o o -o o o o o o o 0 o o o o o o o o o o o o 2/ o o o o o o o o o o o o o o o o o o .0 o o o o o o Patented 'Nov. 18, 1 93 UNITED STATES e HARLAN w. How,]or BUFFALO, NEW YoRKQ ssIeNoR TOBUFIALQLFOUNDRY & MA

CHINE COMPANY, or BUFFALO, NEW Y R QA CORPORATION or NEW YORK and communicating at its upper and lower EvAPo zAToal 5 1 Application ma immar 12,1927. iseiiaino. 160,748. I

This invention relatesto an evaporator of;

a usual window's18 to'permit of observing .the

the type which-is provided with a plurality of small up-take tubes arranged in aheating chamber and adapted to'carry, the liquor upwardly from a lower return chambertoan upper vapor chamber, and a large downtakej.

tube arranged within the heating chamber ends with said vapor and return chambers,

respectively.

Heretofore ithas been customary to employ an ordinary marine propeller either in the downtake tube orimmediately below the same to assist in circulating the liquor, but

this organization is very ineflicient and wastetion, on an enlarged scale, taken on line 3-8' iul of power. a d 1 The object of this invention is to provide an impeller which Virtually createsa static head underneath the tube sheet a-tthelower upward circulation, thereby increasing the eiiiclency'and saving power, and obtalnlng a more rapld circulation and a correspondsurface.

In the accompanying drawings: Figure 11s a vertical section of an evapimprovement. Figure 3 is a horizontalsec- Fig. 1. "Figure 4; is: a plan view, 'on an en .lar ed scale, of the impeller. I

bimilar characters of reference indicate like parts in the several figures of the draw- The numeral 10 represents a heating chainber which is adapted to receive steam or other heating agent from any suitable source through an inlet 11 in its side wall12 and dis:

charge the water of condensation through a 5 pipe 13 andanytrapped air through-a vent pipe 14.

Above the heating chamberis arranged a vapor chamber 9 in which the-vapors from the liquor are drawnof'f by any suitable ends of the small up-take tubes instead or depending on velocity to create the necessary ing increase in the capacity of the heating means through a vapor outlet 15 in the top 16 of the vapor chamber. [The side wall 17 a the wartime is P vi with the' conditionlof the liquor as evaporation promally closed: by a cover20. I

; A plurality of smallupright up-taketubes 21 are arrangedinanannular. group within the heating chamber adjacent to theouter 'wallthere of, which tubes have their upper fends communicating with the vapor-chant ber andsecuredan an upper flue sheet 8 separatmgxthe. heat ng and vapor chambers whilethelowerends 'openinto the return chamber and are secured in the lower flue turn chambers. d

Arranged centrally within the heating chamberisfa large down-take tub623-Wl1lCl1 has itsupperand lower end. communicating sheet 22"which separates the heating and re-,

with the vapor and return chambers and secure din the upper and lower fiuesheets.

Myimproved means for producing ailnore rapid circulation of the liquor through the tubes,vapor chamber and return chamber 1 are constructed as follows Extending downwardly from the lower end of the large central down-take tubeis an impeller casing, the central part 7 'ofwhich is contra'cted to a diameter somewhat smaller than the bore of the downtah'efltube while its 'upperpart 24 flares upwardlyto adiameter corresponding to thebore of the downtake tube and'the lower part 25 o'f-the casing separately from the downtake'tube and se .with-theldowntake tube, as 'shown in Fig: 2'.

ing is 'a'rota'ry impeller. which [comprises an:

. flares downwardly on a curve-inthe form of a trumpet. This casing may be either formed -Within the lower partofthe impeller casupwardly conedibody 26 which is separated by an intervening space from the lower end of the casing, andia plurality of impeller blades 27; 10f} spiralv .f orm arranged in anannular 7 row a r-he upper side of'theimpeller body.

In its preferred form this driving inechanism consists of an upright shaft .28 journaled in a bearing 29 and packed in a stuffingbox 30 on the bottom of-the return chamber, the upper end of this shaft being secured to the center ofthe impellerbody,;aud the lower end of the same being connected with a driving mechanism. 31 of any ap-. proved character arranged outside oiithe evaporator and-receiving itspower from any suitable source. 5

Upon turning the body and blades of the impeller a powerful down-ward suction is produced in the-downtake tube which causes the'liquorto be drawn. downwardly, discharged laterally through the entire peripheral space between the impeller body and the flared lower end of the casing, and pressed'from the return chamber upwardly through the small lip-take tubes into :the vapor chamber. Theliquor'is by'this means circulated very rapidly and with a saving of about one half the power heretofore re quired to do a given amount ofwork, thereby not only increasing the output of the evaporator but also elfecting a material reduction in the cost of evaporating the liquor. I claim as my invention: 7 r

A circulator for evaporators of thecharacter described, comprising an upright conduit having an upper section having a cylindrical wallof comparatively large diameter, an intermediate section having-a tapering wall which reducesdownwardly from the lower end of said cylindrical wall and a lower sectionhaving a flaring'wallwhich en larges downwardly from thelower small end ofthewall of said intermediate section and extends with its lower edge laterally beyond the wall ofthe upper sectionpanda rotary impeller having-a conical-body arranged belowsaid conduit and-axially in. line therewith and having its point projecting upwardly into the lower, and intermer'liate sections of'said conduitand having itsavall flaring downwardly from said. point at a distancesfroni thewall ofsaidlower conduit section and forming between the latter and the body. of said'impeller; an annular outlet 1 passagewhich in'radial section is wide at .the

top and gradually reduces downwardly ito- V ward the narrow lower end thereof; and

blades arranged on the upper side of said impeller bodyand in tthe downwardly "reducing space between the :"marginal pa'rt thereof and the inner side of the wall of said lower conduit section.

In testimony whereof I hereby affix my signature.

HARLAN W. HOV. 

